The Association of German Librarians (VDB) needed three attempts in 2019 to deliver its yearbook to its members. Names had been assigned to wrong addresses (a typical error if only one column in an Excel cell is sorted and the original line alignment is broken), so that the delivery of the books generated many returns. The fact that the delivery took place over the Christmas holidays made communication with VDB-members more difficult. During holidays, both those responsible for the association and the members had other priorities. Even after the members were informed that they should accept the books sent, even though they were not the correct addressees, not all yearbooks could be delivered in the first round. In the second attempt, a programming error occurred in the reorder form. Those who did not provide a membership number could not be served and had to reorder their volume in February a second time. Overall, the accumulation of shipping problems likely caused irritation among members and considerable costs for the VDB.

The story clearly shows that special care is required when sending out mail. In any case, address data should be saved in read-only form, backed up several times and checked for integrity before dispatch. Software that is used in “customer” contact should be thoroughly tested for functionality before it is used. In this way, errors can be avoided internally and do not have to be ironed out live.